1. Field of the Invention
The present invention relates to a method for controlling equipment arranged in a semiconductor fabrication processing line with an on-line management system and, more particularly, to a method for automatically responding to emergency states of semiconductor fabricating equipment after an interruption in the on-line communication has been restored, through an emergency state monitoring module.
2. Description of the Related Art
Generally, the fabrication of semiconductor devices involves highly precise processes that require finely tuned precision equipment. Several pieces of precision equipment are typically employed in sequence and arranged on a semiconductor processing line. The operation of each piece of precision equipment on the line is closely monitored by operators to maintain and enhance the efficiency of the processing line.
As shown in FIG. 1, conventional fabrication equipment 3 are disposed on a conventional processing line. When a lot 10 of workpieces, such as wafers, are introduced into the equipment 3, the equipment 3 performs a fabrication process on the lot. The equipment 3 is connected on-line to a host computer 1 through an equipment server (not shown). An operator interface (O/I) 2, for example an operator interface personal computer (O/I PC), is also connected on-line to the host computer 1. Through the O/I 2, an operator informs the host computer 1 that a process using the equipment 3 is about to commence. The operator inputs basic manufacture data, e.g., the identification number (ID) of the lot to be processed in the equipment 3 and the ID of the equipment 3 for performing the process with the lot, into the host computer 1.
Then, based on the input basic manufacture data, the host computer 1 searches its data base for the process condition data to be applied to the process on the lot. The host computer 1 immediately downloads these process condition data, including preset process settings, to the equipment. Process settings may include, for example, a desired process time duration or a desired process temperature.
Thereafter, the operator checks the process condition data and inputs a process commencing command or a process terminating command. The lot is then automatically and rapidly routed into and out of the equipment 3. In this manner, the process equipment 3 performs on the workpieces of each lot based on the process settings received.
If any emergency situation, such as operation troubles, occurs in the equipment 3 during the process with the lots 10, the equipment 3 immediately reports the emergency occurrence therein to the host computer 1. The host computer 1 then immediately informs the operator through the O/I 2 that the equipment 3 is in the emergency state. As a result, the operator can take action to handle the emergency and to restore the equipment 3 to the normal state.
However, such a conventional management system suffers from several problems. First, in the event that the on-line communication between the host computer 1 and the equipment 3 is interrupted for more than a certain amount of time, data transmissions between the host computer 1 and the equipment 3 are cut off, and equipment emergency states sent to the host computer 1 during this interval will not be received. Consequently, the emergency state of the equipment 3 recognized by the host computer 1 is the emergency state before the on-line communication was interrupted. After the on-line communication is restored, the emergency state recognized by the host computer 1 can not be considered accurate.
Secondly, in the event that an inaccurate emergency state is transmitted to the operator through the O/I 2, operational problems may occur that the operator can not foresee.
Thirdly, because the emergency state is not reliably accurate after the on-line communication is restored, the operator must check all the equipment one by one to accurately recognize whether any emergency situation has occurred. This results in increased work load for the operator and efforts diverted from other necessary duties.